In recent years, in-ear headphones (also known in the industry as “earbuds”) have gained popularity. This increase in popularity may be partly due to the generally smaller, lighter, and less obtrusive geometry offered by in-ear headphones compared to on-ear and over-ear headphones. Also, some people may prefer the sound generated by in-ear headphones compared to other types of headphones.
Although in-ear headphones offer advantages over other types of headphones, there are also some disadvantages associated with in-ear headphones. Among these disadvantages is the difficulty of designing in-ear headphones that are securely retained in the ears of most or all people. The size and shape of each different person's ear is unique. In fact, the size and shape of one of a person's ears may be different from the size and/or shape of that same person's other ear. Accordingly, retention members for in-ear headphones have been developed for engaging with portions of the outer ear to hold the in-ear headphones in place in or over the ear canal. However, due to the unique shape and size of outer ears of different users, many known retention members having a single size and design are not adequately retained in the ears of many users.